I have a couple of B&W conversion actions (so I cheat a little). After basic conversion I use levels and curves either across the whole image or usually selectively (using layer masks and lassoed selections) to edit the image.
And Seenew, that is a dirty dirty sensor!
Mind sharing a link to any of the actions (if you can even find them)?
Personally, I do my B&W conversions like this:
1. Layer -> New Adjustment Layer -> Hue/Saturation
2. Click OK when the dialog box pops up
3. Make no changes and click OK
4. Layer -> New Adjustment Layer -> Hue/Saturation
5. Change the Mode from "normal" to "color"
6. Click OK
7. Bring the saturation all the way back to -100
8. Click OK
9. Double-click back on the Hue/Saturation layer you didn't touch
10. Adjust the hue slider until the colors look the way you want them to.
11. Click OK
12. Done!